My guess is because it's supposed to be a Dust a la Guilty Gear, considering that RF is supposed to be a Robo-Ky homage. (Robo-Ky Dust has a similar animation as well.) I think it's pretty self-explanatory too: HK on a default arcade stick is exactly where Dust would be.
Can you still do this if you have 2 or 3 heads or does it only work with 1?
I used to do delay j.LP j.HK to get this mixup but it only worked on lights and I was too lazy to look into how to make it work on mids and heavies. This is gdlk, tyvm.
How does this option select work?
He didn't say that, he said (probably not exact words but paraphrasing) that it's good to catch people as they come in swinging buttons in neutral, kind of like a DP assist. If they hit Robo in the startup they're committed to the move (unless they cancel it to something that will avoid the mine drop) so the mine comes down and explodes, granting you a combo.@Mike_Z hey didnt you say you had Mine placement be invincible...? I'm determined to find it and i will :P but cant atm.
yeah her wakeup is so yucky :(